i have basically the exact same lighting setup except i have 6 - 24" Flourescent tubes, 2 of them are indoor plant bulbs and 4 cool white, at a week and a half my plant was about that size if not bigger. I keep them about 2 inches from the light at all times 24/0 with a constant fan blowing on them giving a nice little breeze constant. I am using somewhat of a hydroponics setup but those look really small for that long. If you saw my 2 plants now vegging for 3 1/2 weeks under the setup above, you would understand why i said yours are below normal growth